Lid assembly for a processing system to facilitate sequential deposition techniques

ABSTRACT

A lid assembly for a semiconductor processing system is provided. The lid assembly generally includes a lid having first and second opposed surfaces, a plurality of controllable flow channels extending from the first and second opposed surfaces and a gas control system disposed on the first surface and operably opening and closing the channels. The gas control system includes a gas manifold disposed on the lid, at least one valve coupled to the gas manifold and adapted to control a flow through one of the flow channels, a reservoir fluidly connected to the gas manifold, and a precursor source fluidly connected to the reservoir.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of pending U.S. patent applicationSer. No. 10/016,300, filed Dec. 12, 2001, which claims benefit of U.S.Provisional Application No. 60/305,970, filed Jul. 16, 2001, which areboth incorporated herein by reference.

Additionally, this application is related to U.S. Pat. No. 6,660,126,U.S. patent application Ser. No. 09/798,258, entitled “ProcessingChamber and Method of Distributing Process Fluids Therein to FacilitateSequential Deposition of Films,” filed on Mar. 2, 2001, published asU.S. 20020121241, and U.S. Pat. No. 6,333,123, all of which areincorporated herein by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to semiconductor processing. More particularly,this invention relates to a processing system and method of distributingfluid therein to facilitate sequential deposition of films on asubstrate.

2. Description of the Related Art

The semiconductor processing industry continues to strive for largerproduction yields while increasing the uniformity of layers deposited onsubstrates having increasingly larger surface areas. These same factorsin combination with new materials also provide higher integration ofcircuits per unit area of the substrate. As circuit integrationincreases, the need for greater uniformity and process control regardinglayer thickness rises. As a result, various technologies have beendeveloped to deposit layers on substrates in a cost-effective manner,while maintaining control over the characteristics of the layer.Chemical Vapor Deposition (CVD) is a common deposition process employedfor depositing layers on a substrate. CVD is a flux-dependent depositiontechnique that requires precise control of the substrate temperature andprecursors introduced into the processing chamber in order to produce adesired layer of uniform thickness. These requirements become morecritical as substrate size increases, creating a need for morecomplexity in chamber design and fluid flow technique to maintainadequate uniformity.

A variant of CVD that demonstrates superior step coverage is asequential deposition technique known as Atomic Layer Deposition (ALD).ALD has steps of chemisorption that deposit monolayers of reactiveprecursor molecules on a substrate surface. To that end, a pulse of afirst reactive precursor is introduced into a processing chamber todeposit a first monolayer of molecules on a substrate disposed in theprocessing chamber. A pulse of a second reactive precursor is introducedinto the processing chamber to form an additional monolayer of moleculesadjacent to the first monolayer of molecules. In this manner, a layer isformed on a substrate by alternating pulses of an appropriate reactiveprecursor into a deposition chamber. Each injection of a reactiveprecursor is separated by an inert fluid purge to provide a new atomiclayer additive to previous deposited layers to form a uniform layer onthe substrate. The cycle is repeated to form the layer to a desiredthickness. The control over the relatively small volume of gas utilizedin each pulse is problematic. Pulse frequency is limited by the responsetimes of valves and flow lag within the chamber's gas delivery system.The lag is at least partially due to the relative remote position ofcontrol valves to the process chamber. Consequently, ALD techniquesresult in a deposition rate that is much lower than typical CVDtechniques.

Therefore, a need exists to reduce the time required to deposit filmsemploying sequential deposition techniques.

SUMMARY OF THE INVENTION

Provided is a lid assembly for a semiconductor system, an exemplaryembodiment of which includes a support having opposed first and secondsurfaces, with a valve coupled to the first surface. A baffle plate ismounted to the second surface. The valve is coupled to the support todirect a flow of fluid along a path in an original direction and at aninjection velocity. The baffle plate is disposed in the path to dispersethe flow of fluid in a plane extending transversely to the originaldirection. The proximity of the valve to the baffle plate allowsenhanced rate and control of fluid disposed through the lid assembly.

In one aspect of the invention, one embodiment of a lid assembly for asemiconductor processing system includes a lid having a gas manifoldcoupled to a first surface and a baffle plate coupled to a secondsurface. The gas manifold includes a body having a first channel, asecond channel and a third channel extending therethrough. The baffleplate includes a recess formed in a first side of the baffle plate anddefining a plenum with a second surface of the lid. The plenumcommunicates with the first, second and third channels via a pluralityof inlet channels disposed in the lid. The baffle plate has a centerpassage disposed therethrough which provides a singular passagewaybetween the plenum and the second side of the baffle plate. Optionally,any combination of the lid, gas manifold or baffle plate mayadditionally include features for controlling the heat transfertherebetween.

In another aspect of the invention, a baffle plate for distributinggases into a semiconductor processing chamber is provided. In oneembodiment, the baffle plate includes a plate having a first side and asecond side. A recess is formed in the first side and defines a plenumadapted to receive gases prior to entering the processing chamber. Acenter passage is disposed through the plate concentrically and isconcentric with the recess. The center passage provides a singlepassageway between the recess and the second side of the plate.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the invention, briefly summarizedabove, may be had by reference to the embodiments thereof which areillustrated in the appended drawings. It is to be noted, however, thatthe appended drawings illustrate only typical embodiments of thisinvention and are therefore not to be considered limiting of its scope,for the invention may admit to other equally effective embodiments.

FIG. 1 is a simplified top perspective view of a plasma-basedsemiconductor processing system in accordance with one embodiment of thepresent invention;

FIG. 2 is a top perspective view of one embodiment of a lid assembly ofthe invention;

FIG. 3 is a sectional view of one embodiment of a lid assembly of theinvention;

FIG. 4 is a sectional view of the embodiment of the lid assembly of FIG.3; and

FIG. 5A depicts a bottom view of one embodiment of a gas manifold;

FIG. 5B depicts a partial sectional view of the gas manifold taken alongsection line 5B-5B of FIG. 5A;

FIG. 6 is a perspective view of one embodiment of a baffle plate;

FIG. 7 is a sectional view of the baffle plate taken along section line7-7 of FIG. 6;

FIG. 8 is a partial sectional view of one embodiment of a mixing lip;and

FIG. 9 is a cross-sectional view of the processing chamber of FIG. 1connected to various subsystems associated with system.

To facilitate understanding, identical reference numerals have beenused, wherever possible, to designate identical elements that are commonto the figures.

DETAILED DESCRIPTION

Referring to FIG. 1, a semiconductor processing system 10 in accordancewith one embodiment of the present invention includes an enclosureassembly 12 formed from a process-compatible material, such as aluminumor anodized aluminum. The enclosure assembly 12 includes a housing 14,defining a processing chamber 16 with an opening 44 selectively coveredand a vacuum lid assembly 20. The vacuum lid assembly 20 is pivotallycoupled to the housing 14 via hinges 22. A handle 24 is attached to thevacuum lid assembly 20 opposite the hinges 22. The handle 24 facilitatesmoving the vacuum lid assembly 20 between opened and closed positions.In the opened position, the interior of the chamber 16 is exposed. Inthe closed position shown in FIG. 1, the vacuum lid assembly 20 coversthe chamber 16 forming a fluid-tight seal with the housing 14. In thismanner, a vacuum formed in the processing chamber 16 is maintained asthe vacuum lid assembly 20 seals against the housing 14.

To facilitate access to processing chamber 16 depicted in FIG. 1,without compromising the fluid-tight seal between vacuum lid assembly 20and housing 14, a slit valve opening 44 is disposed in housing 14, aswell as a vacuum lock door (not shown). Slit valve opening 44 allowstransfer of a wafer (not shown) between processing chamber 16 and theexterior of system 10. Any conventional wafer transfer device (notshown) may achieve the aforementioned transfer. An example of aconventional wafer transfer device is described in commonly assignedU.S. Pat. No. 4,951,601, issued Aug. 20, 1990 to Maydan, et al., thecomplete disclosure of which is incorporated herein by reference.

FIG. 2 is a top perspective view of one embodiment of a vacuum lidassembly 20. The vacuum lid assembly 20 includes a lid 20 a and aprocess fluid injection assembly 30 to deliver reactive, carrier, purge,cleaning and/or other fluids into the processing chamber 16. Lid 20 aincludes opposing surfaces 21 a and 21 b. The fluid injection assembly30 includes a gas manifold 34 mounting a plurality of control valves, 32a, 32 b and 32 c, and a baffle plate 36 (shown in FIG. 3). Valves 32 a,32 b and 32 c provide rapid and precise gas flow with valve open andclose cycles of less than about one second, and in one embodiment, ofless than about 0.1 second. In one embodiment, the valves 32 a, 32 b and32 c are surface mounted, electronically controlled valves. One valvethat may be utilized is available from Fujikin of Japan as part numberFR-21-6.35 UGF-APD. Other valves that operate at substantially the samespeed and precision may also be used.

The lid assembly 20 further includes one or more, (two are shown inFIG. 1) gas reservoirs 33, 35 which are fluidically connected betweenone or more process gas sources and the gas manifold 34. The gasreservoirs 33, 35 provide bulk gas delivery proximate to each of thevalves 32 a, 32 b, 32 c. The reservoirs 33, 35 are sized to insure thatan adequate gas volume is available proximate to the valves 32 a, 32 b,32 c during each cycle of the valves 32 a, 32 b and 32 c duringprocessing to minimize time required for fluid delivery therebyshortening sequential deposition cycles. For example, the reservoirs 33,35 may be about 5 times the volume required in each gas delivery cycle.

Gas lines 37, 39 extend between connectors 41, 43 and the reservoirs 33,35 respectively. The connectors 41, 43 are coupled to the lid 20 a. Theprocess gases are typically delivered through the housing 14 to theconnectors 41, 43 before flowing into the reservoirs 33, 35 through thegas lines 37, 39.

Additional connectors 45, 47 are mounted adjacent the gas manifold 34down stream from the reservoirs 33, 35 and connect to the reservoirs bygas lines 49, 51. The connectors 45, 47 and gas lines 49, 51 generallyprovide a flowpath for process gases from the reservoir 33, 35 to thegas manifold 34. A purge gas line 53 is similarly connected between aconnector 55 and a connection 57 on the gas manifold 34. In oneembodiment, a tungsten source gas, such as tungsten hexafluoride, isconnected to the first reservoir 33 and a reducing gas such as silane ordiborane is connected to the second reservoir 35.

FIGS. 3 and 4 are partial sectional views of the vacuum lid assembly 20.The gas manifold 34 includes a body defining three valve mountingsurfaces 59, 61, 64 (mounting surface 64 is shown in FIG. 4) and anupper surface 63 for mounting an upper valve 65. The gas manifold 34includes three pairs of gas channels 67 a, 67 b, 69 a, 69 b, 69 c, 71 a,71 b (71 a and 71 b are shown on FIG. 4) that fluidly couple the twoprocess gases and a purge gas (shown as fluid sources 68 a-c in FIG. 9)to the interior of the processing chamber 16 controllably through thevalves 32 a, 32 b, 32 c, thereby allowing thermal conditioning of thegases by the gas manifold 34 before reaching the valves 32 a, 32 b, 32c. Gas channels 67 a, 69 a, 71 a (also termed thermal conditioningchannels) are fluidly coupled to the connectors 45, 47, 57 and providepassage of gases through the gas manifold 34 to the valves 32 a, 32 b,32 c. Gas channels 67 b, 69 b and 71 b deliver gases from the valves 32a, 32 b, 32 c through the gas manifold 34. The gas channel 71 b deliversgas from the valve 32 c through the gas manifold 34 and into a gaschannel 73 passing through a member 26. The channels 67 b, 69 b and 73are fluidly coupled to a respective inlet passage 302, 304 and 306disposed through the lid 20 a. Gases or other fluids flowing through theinlet passages 302, 304 and 306 flow into a plenum or region 308 definedbetween the lid 20 a and baffle plate 36 before entering the chamber 16.

The channel 73 additionally is coupled to the upper surface 63. Thevalve 65 is disposed between the upper surface 63 of the gas manifold 34and a cleaning source 38. The cleaning source 38 is a compact system forproviding cleaning reagents, typically in the form of fluorine orfluorine radicals, for removing contaminants and deposition byproductsfrom the chamber 16. In one embodiment, the cleaning source 38 is aremote plasma source that typically includes subsystems (not shown) suchas a microwave generator in electrical communication with a plasmaapplicator, an autotuner and an isolator. The gas channel 73 throughwhich the cleaning gases are delivered from the cleaning source 38 isadditionally connected with the gas channel 71 b that delivers purge gasto the chamber 16 through the plenum 308 disposed in the baffle plate36. In this manner, as purge gas is delivered to the chamber 16, anycleaning reagents remaining in the channel 73 between the gas channel 71b and the chamber 16 may be flushed and exhausted from the chamber 16prior to the next deposition process.

The gas manifold 34 further includes a conduit 75 for flowing a heattransfer medium therethrough, thus allowing temperature control of thegas manifold 34. In tungsten deposition processes, for example, the gasmanifold 34 is typically cooled. For other processes, such as titaniumnitride deposition, the gas manifold 34 may be heated to preventcondensation of the reactive gases within the manifold. To furtherassist in temperature control of the gas manifold 34, a lower surface 77of the gas manifold 34 may be configured to tailor the surface areacontact with a first surface 42 of the lid 20 a, thus controlling thethermal transfer between the housing 14 and manifold through the lid 20a. Alternatively, the housing 14 and manifold 34 may be configured tomaximize the contact area.

Optionally, a plurality of recesses 28 may be formed in a second surface44 of the lid 20 a that contacts the baffle plate 36. The recesses 28allow the contact area between the baffle plate 36 and lid 20 a to betailored to promote a desired rate of heat transfer. The baffle plate 36may alternately be configured to control the contact area with the lid20 a as described with reference to FIGS. 6 and 7 below.

Referring to FIGS. 5A and 5B, the lower surface 77 of the gas manifold34 is illustrated configured to minimize surface area contact with thelid 20 a. Each of the three gas channels 67 b, 69 b, 73 passrespectively through bosses 502, 504 and 506 that project from the gasmanifold 34. Each boss 502, 504 and 506 has an o-ring chase 79, 81, 83that respectively surrounds each gas channel 67 b, 69 b, 73 to preventfluids passing therethrough from leaking between the gas manifold 34 andthe lid 20 a. A mounting surface 508 surrounds the bosses 502, 504 and506 and includes a plurality of mounting holes 510 which facilitatecoupling the gas manifold 34 to the cover 20 a. In one embodiment, thegas manifold 34 is fastened by screws threading into blind holes formedin the lid 20 a (screws and blind holes not shown). As the bosses 502,504 and 506 and mounting surface 508 provide a controlled contact areabetween the gas manifold 34 and the cover 20 a, the thermal transfertherebetween can be minimized. The contact area between the gas manifold34 and the cover 20 a may utilize other geometries to tailor the heattransfer therebetween. For example, the lower surface 77 of the gasmanifold 34 can be planar to provide maximum contact area with the lid20 a and thus maximize heat transfer between the lid 20 a and the gasmanifold 34.

Returning to FIG. 4, temperature control of system 10 may be achieved byflowing a heat transfer medium through a temperature control channel 20g disposed within the lid 20 a. The temperature control channel 20 g isin fluid communication with heat transfer medium supply (not shown) thatprovides and/or regulates the temperature of the heat transfer mediumflowing through the channel 20 g to control (i.e., heat, cool ormaintain constant) the temperature of the lid 20 a.

FIGS. 6 and 7 depict one embodiment of the baffle plate 36. The baffleplate 36 is coupled to the lid 20 a opposite the gas manifold 34. Thebaffle plate 36 is generally comprised of a process compatible materialsuch as aluminum and is utilized to mix and uniformly distribute gasesentering the chamber 16 from the gas manifold 34. The baffle plate 36may be removed from the lid 20 a for cleaning and/or replacement.Alternatively, the baffle plate 36 and lid 20 a may be fabricated as asingle member.

The baffle plate 36 is generally annular and includes a first side 36 adisposed proximate the lid 20 a and a second side 36 b generally exposedto interior of the processing chamber 16. The baffle plate 36 has apassage 700 disposed between the first side 36 a and the second side 36b. A recess 702, typically concentric with the passage 700, extends intothe first side 36 a. The recess 702 and lid 20 a define a plenumtherebetween. The recess 702, typically circular in form, is configuredto extend radially from a center line of the baffle plate 36 to adiameter that extends beyond the inlet passages 302, 304, 306 disposedin the lid 20 a so that gases flowing from the inlet passages enters theplenum and exits through the passage 700.

A bottom 712 of the recess 702 defines a mixing lip 704 that extendsradially inward into the passage 700. The transition from a wall 714 ofthe recess 702 to the bottom 712 includes a radius 710 to assist indirecting fluid flow within the recess 702 while maximizing the sweptvolume of the recess 702. Gases flowing into the plenum from the inletpassages 302, 304, 306 are re-directed by the flat surface of the mixinglip 704 generally towards the center of the recess 702 before passingthrough the passage 700 and into the process chamber 16. The recess 702combined with a singular exit passage for delivering gases to thechamber 16 (e.g., the passage 700) advantageously reduces the surfacearea and orifices requiring purging and cleaning over conventionalshowerheads having multiple orifices for gas delivery.

FIG. 8 depicts a partial sectional view of one embodiment of the mixinglip 704. The mixing lip 704 may include an optional sculptured surface802 that directs the gas flows towards one another or induces turbulenceto enhance mixing and/or cleaning. The sculptured surface 802 mayincludes any one or combination of turbulence-inducing features such asone or more bumps, grooves, projections, indentations, embossed patternsand the like. Alternatively, bottom 712 of the recess 702 defining themixing lip 704 may be smooth. In one embodiment, the mixing lip 704directs gases moving substantially axially from the lid 20 atransversely towards the center of the passage 700 in either a turbulentflow as depicted by flow lines 804, laminar flow or combination thereof,where the converging gas flows mix before exiting the passage 700.

The mixing lip 704 may include a rounded tip 806 to assist in directingthe flow through the passage 700 and into the chamber 16 with minimalpressure drop. In one embodiment, the mixing lip 704 includes atransition angle 808 between the tip 804 and the second side 36 b of thebaffle plate 36 to enhance the radial flow and uniformity of fluidsexiting the passage 700 and into the chamber 16.

Returning to FIGS. 6 and 7, the first side 36 a of the baffle plate 36may additionally include features for reducing the contact area betweenthe baffle plate 36 and the lid 20 a. Providing reduced contact areaallows the baffle plate 36 to be operated at a higher temperature thanthe lid 20 a, which in some processes enhances deposition performance.In the embodiment depicted in FIG. 7, the first side 36 a of the baffleplate 36 includes a plurality of bosses 602, each having a mounting hole604 passing therethrough. The bosses 602 allow the baffle plate 36 to becoupled to the lid 20 a by fasteners passing through the mounting holes604 into blind threaded holes formed in the lid 20 a (fasteners andthreaded holes not shown). Additionally, a ring 606 projects from thefirst side 36 a and circumscribes the recess 702. The ring 606 andbosses 602 project to a common elevation that allows the baffle plate 36to be coupled to the lid 20 a in a spaced-apart relation. Thespaced-apart relation and the controlled contact area permit controlledthermal transfer between the baffle plate 36 and the lid 20 a.Accordingly, the contact area provided by bosses 602 and the ring 606may be designed to tailor the amount and location of the solid to solidcontact area available for thermal transfer between the baffle plate 36and the lid 20 a as a particular deposition process requires.

Referring to FIG. 9, disposed within processing chamber 16 is aheater/lift assembly 46 that includes a wafer support pedestal 48connected to a support shaft 48 a and conduit 46 a. The support pedestal48 is positioned between the shaft 48 a and the vacuum lid assembly 20when the vacuum lid assembly 20 is in the closed position. The supportshaft 48 a extends from the wafer support pedestal 48 away from vacuumlid assembly 20 through a passage formed in the housing 14. A bellows 50is attached to a portion of the housing 14 disposed opposite to the lidassembly 20 to prevent leakage into the chamber 16 from between thesupport shaft 48 a and housing 14. The heater/lift assembly 46 may bemoved vertically within the chamber 16 so that a distance betweensupport pedestal 48 and vacuum lid assembly 20 may be controlled. Asensor (not shown) provides information concerning the position ofsupport pedestal 48 within processing chamber 16. An example of alifting mechanism for the support pedestal 48 is described in detail inU.S. Pat. No. 5,951,776, issued Sep. 14, 1999, to Selyutin et al.,entitled “Self-Aligning Lift Mechanism,” which is hereby incorporated byreference in it entirety.

The support pedestal 48 includes an embedded thermocouple 50 a that mayused to monitor the temperature thereof. For example, a signal from thethermocouple 50 a may be used in a feedback loop to control powerapplied to a heater element 52 a by a power source 52. The heaterelement 52 a may be a resistive heater element or other thermal transferdevice disposed in or in contact with the pedestal 48 utilized tocontrol the temperature thereof. Optionally, support pedestal 48 may beheated using a heat transfer fluid (not shown).

The support pedestal 48 may be formed from any process-compatiblematerial, including aluminum nitride and aluminum oxide (Al₂O₃ oralumina) and may also be configured to hold a substrate thereonemploying a vacuum, i.e., support pedestal 48 may be a vacuum chuck. Tothat end, support pedestal 48 may include a plurality of vacuum holes(not shown) that are placed in fluid communication with a vacuum source,such as pump system via vacuum tube routed through the support shaft 48a.

A liner assembly is disposed in the processing chamber 16 and includes acylindrical portion 54 and a planar portion. The cylindrical portion 54and the planar portion may be formed from any suitable material such asaluminum, ceramic and the like. The cylindrical portion 54 surrounds thesupport pedestal 48. The cylindrical portion 54 additionally includes anaperture 60 that aligns with the slit valve opening 44 disposed a sidewall 14 b of the housing 14 to allow entry and egress of substrates fromthe chamber 16.

The planar portion extends transversely to the cylindrical portion 54and is disposed against a chamber bottom 14 a of processing chamber 16disposed opposite to lid assembly 20. The liner assembly defines achamber channel 58 between the housing 14 and both cylindrical portion54 and planar portion. Specifically, a first portion of channel 58 isdefined between the chamber bottom 14 a and planar portion. A secondportion of channel 58 is defined between the side wall 14 b of thehousing 14 and the cylindrical portion 54. A purge gas is introducedinto the channel 58 to minimize inadvertent deposition on the chamberwalls along with controlling the rate of heat transfer between thechamber walls and the liner assembly.

Disposed along the side walls 14 b of the chamber 16 proximate the lidassembly 20 is a pumping channel 62. The pumping channel 62 includes aplurality of apertures, one of which is shown as a first aperture 62 a.The pumping channel 62 includes a second aperture 62 b that is coupledto a pump system 18 by a conduit 66. A throttle valve 18A is coupledbetween the pumping channel 62 and the pump system 18. The pumpingchannel 62, throttle valve 18A and pump system 18 control the amount offlow from the processing chamber 16. The size and number and position ofapertures 62 a in communication with the chamber 16 are configured toachieve uniform flow of gases exiting the lid assembly 20 over supportpedestal 48 and substrate seated thereon. A plurality of supplies 68 a,68 b and 68 c of process and/or other fluids, is in fluid communicationwith one of valves 32 a, 32 b or 32 c through a sequence of conduits(not shown) formed through the housing 14, lid assembly 20, and gasmanifold 34.

A controller 70 regulates the operations of the various components ofsystem 10. The controller 70 includes a processor 72 in datacommunication with memory, such as random access memory 74 and a harddisk drive 76 and is in communication with at least the pump system 18,the power source 52, and valves 32 a, 32 b and 32 c.

Although any type of process fluid may be employed, one example ofprocess fluids are B₂H₆ gas and WF₆ gas, and a purge fluid is Ar gas. N₂may also be used as a purge gas. The chamber pressure is in the range of1-5 Torr, and the pedestal 48 is heated in the range of 3500 to 400° C.Each of the process fluids is flowed into the processing chamber 16 witha carrier fluid, such as Ar. It should be understood, however, that thepurge fluid might differ from the carrier fluid, discussed more fullybelow.

One cycle of the sequential deposition technique in accordance with thepresent invention includes flowing the purge fluid, Ar, into theprocessing chamber 16 during time t₁, before B₂H₆ is flowed into theprocessing chamber 16. During time t₂, the process fluid B₂H₆ is flowedinto the processing chamber 16 along with a carrier fluid, which in thisexample is Ar. After the flow of B₂H₆ terminates, the flow of Arcontinues during time t₃, purging the processing chamber 16 of B₂H₆.During time t₄, the processing chamber 16 is pumped so as to remove allprocess fluids. After pumping of the processing chamber 16, the carrierfluid Ar is introduced during time t₅, after which time the processfluid WF₆ is introduced into the processing chamber 16, along with thecarrier fluid Ar during time t₆. After the flow of WF₆ into theprocessing chamber 16 terminates, the flow of Ar continues during timet₇. Thereafter, the processing chamber 16 is pumped so as to remove allprocess fluids therein, during time t₈, thereby concluding one cycle ofthe sequential deposition technique in accordance with the presentinvention. This sequence of cycles is repeated until the layer beingformed thereby has desired characteristics, such as thickness,conductivity and the like. It can be seen that the time required duringeach period t₁-t₇ greatly affects the throughput of system 10. Tomaximize the throughput, the lid assembly 20 and the injection assembly30 are configured to minimize the time required to inject process fluidsinto the processing chamber 16 and disperse the fluids over the processregion proximate to the support pedestal 48. For example, the proximityof the reservoirs 33, 35 and valves 32 a-b to the gas manifold 34 reducethe response times of fluid delivery, thereby enhancing the frequency ofpulses utilized in ALD deposition processes. Additionally, as the purgegases are strategically delivered through the lower portion of thepassage 73, sweeping of cleaning agents from the gas manifold 34 andbaffle plate 36 is ensured and process uniformity with smaller processgas volumes is enhanced.

Although the invention has been described in terms of specificembodiments, one skilled in the art will recognize that variousmodifications may be made that are within the scope of the presentinvention. For example, although three valves are shown, any number ofvalves may be provided, depending upon the number of differing processfluids employed to deposit a film. Therefore, the scope of the inventionshould not be based upon the foregoing description. Rather, the scope ofthe invention should be determined based upon the claims recited herein,including the full scope of equivalents thereof.

1. A lid assembly for a substrate processing system, the lid assemblycomprising: a lid having first and second opposed surfaces; a pluralityof controllable flow channels extending from the first and secondopposed surfaces; and a gas control system disposed on the first surfaceand operably opening and closing the channels, wherein the gas controlsystem comprises: a gas manifold disposed on the lid; at least one valvecoupled to the gas manifold and adapted to control a flow through one ofthe flow channels; a reservoir fluidly connected to the gas manifold;and a precursor source fluidly connected to the reservoir.
 2. The lidassembly of claim 1, wherein the gas manifold comprises: an uppersurface and a lower surface; a first channel, a second channel and athird channel each extending through the gas manifold and exiting thelower surface; and a fourth channel extending from the upper surface andcoupling to the third channel.
 3. The lid assembly of claim 2, whereinthe gas control system further comprises: a remote plasma source fluidlycoupled to the fourth channel.
 4. The lid assembly of claim 2, whereinthe gas manifold further comprises: a conduit disposed therein adaptedto flow a heat transfer fluid therethrough.
 5. The lid assembly of claim1, wherein the reservoir is positioned on the lid.
 6. The lid assemblyof claim 5, wherein the reservoir is connected between the precursorsource and the gas manifold.
 7. The lid assembly of claim 6, wherein asecond reservoir is fluidly connected to the gas manifold and to asecond precursor source.
 8. A lid assembly for a substrate processingsystem, the lid assembly comprising: a lid having first and secondopposed surfaces, the first and second opposed surfaces having a firstinlet channel, a second inlet channel and a third inlet channel disposedtherethrough; a gas manifold coupled to the first surface of the lid,the gas manifold comprising: a body having an upper surface and lowersurface; and a first channel, a second channel, and a third channel eachextending through the gas manifold to the lower surface; a valve coupledto the gas manifold; and a gas reservoir fluidly connected to the gasmanifold.
 9. The lid assembly of claim 8, wherein a precursor source isfluidly connected to the gas reservoir.
 10. The lid assembly of claim 9,wherein the gas reservoir is between the precursor source and the gasmanifold.
 11. The lid assembly of claim 10, further comprising: athermal conditioning channel disposed in the gas manifold fluidlycoupling the valve and the gas reservoir.
 12. The lid assembly of claim11, wherein the gas manifold further comprises a fourth channel coupledbetween the upper surface and the third channel.
 13. The lid assembly ofclaim 12, further comprising: a remote plasma source fluidly coupled tothe fourth channel.
 14. The lid assembly of claim 10, wherein a secondreservoir is fluidly connected to the gas manifold and to a secondprecursor source.
 15. A lid assembly for a substrate processing system,the lid assembly comprising: a lid having first and second opposedsurfaces, the first and second opposed surfaces having a plurality ofinlet channels disposed therethrough; a valve; a gas manifold coupled tothe first surface of the lid, the gas manifold comprising: a body havingan upper surface and lower surface; a plurality of gas channelsextending through the gas manifold to the lower surface; and a thermalconditioning channel disposed in the gas manifold and fluidly coupled toat least one of the plurality of gas channels by the valve; and a gasreservoir fluidly connected to the gas manifold and to the at least oneof the plurality of gas channels.
 16. The lid assembly of claim 15,wherein a precursor source is fluidly connected to the gas reservoir.17. The lid assembly of claim 16, wherein the gas reservoir is betweenthe precursor source and the gas manifold.
 18. The lid assembly of claim17, wherein the gas reservoir is positioned on the lid.
 19. The lidassembly of claim 17, wherein a second reservoir is fluidly connected tothe gas manifold and to a second precursor source.
 20. The lid assemblyof claim 17, further a remote plasma source fluidly coupled to the atleast one of the plurality of gas channels.